package state;

import bean.SensorReading;
import org.apache.flink.api.common.functions.MapFunction;
import org.apache.flink.streaming.api.checkpoint.ListCheckpointed;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;

import javax.swing.*;
import java.awt.*;
import java.util.Collections;
import java.util.List;

/**
 * @Description: TODO QQ1667847363
 * @author: xiao kun tai
 * @date:2021/11/4 19:46
 */
public class State1_OperatorState {

    public static void main(String[] args) throws Exception {
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        env.setParallelism(1);


        DataStream<String> inputStream = env.socketTextStream("192.168.88.106", 7777);

        DataStream<SensorReading> dataStream = inputStream.map(line -> {
            String[] fields = line.split(",");
            return new SensorReading(fields[0], new Long(fields[1]), new Double(fields[2]));
        });


        //定义一个有状态的map操作，统计当前分区数
        SingleOutputStreamOperator<Integer> resultStream = dataStream.map(new MyCountMapper());


        resultStream.print();
        env.execute();
    }

    //自定义MapFunction
    public static class MyCountMapper implements MapFunction<SensorReading, Integer>, ListCheckpointed<Integer> {

        //定义一个本地变量
        private Integer count = 0;

        @Override
        public Integer map(SensorReading sensorReading) throws Exception {
            count++;
            return count;
        }


        @Override
        public List<Integer> snapshotState(long l, long l1) throws Exception {
            return Collections.singletonList(count);
        }

        @Override
        public void restoreState(List<Integer> list) throws Exception {
            for (Integer integer : list) {
                count += integer;
            }
        }
    }

}
